from django.contrib.postgres.search import SearchVector
from django.shortcuts import render

# Create your views here.
from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger


from django.db.models import Count



from .models import Post
from django.shortcuts import render, get_object_or_404
from django.core.mail import send_mail
from .forms import EmailPostForm, CommentForm


from taggit.models import Tag
from .forms import EmailPostForm, CommentForm, SearchForm




def post_list(request, tag_slug=None):
 posts = Post.published.all()

 tag = None
 # 如果请求中有tag_slug，则获取标签并按标签过滤文章数据 
 if  tag_slug: 
       # 获取标签
       tag = get_object_or_404(Tag, slug=tag_slug)
       # 按标签过滤文章
       posts = posts.filter(tags=tag)

 paginator = Paginator(posts, 3)
 page = request.GET.get('page')
 try:
  posts =paginator.page(page)
 except PageNotAnInteger:
  posts =paginator.page(1)
 except EmptyPage:
  posts = paginator.page(paginator.num_pages)
  


 return render(request, 'blog/post/list.html', {'posts': posts,'page': page,'tag':tag})




def post_detail(request, year, month, day, post):
 post = get_object_or_404(Post, slug=post, status='published',
 publish__year=year,
 publish__month=month,
 publish__day=day)
 
 
 # 找到所有相似文章
# 找到当前文章的标签编号
 post_tags_ids = post.tags.values_list('id', flat=True)
# 找到包含当前文章任意标签的文章集合（除当前文章外）
 similar_posts = Post.published.filter(tags__in=post_tags_ids)\
                            .exclude(id=post.id)
# 对相似文章按照相同标签数量进行排序，取前4个，相同标签数量使用聚合函数Count
# 计算后保存在same_tags中，以便后续使用
 similar_posts = similar_posts.annotate(same_tags=Count('tags'))\
                            .order_by('-same_tags','-publish')[:4]
 
 
 
 
 
 
 
 comments = post.comments.filter(active=True)
# 创建一个新评论变量，默认为None
 new_comment = None
 # 如果请求类型是POST，则获取请求中的评论数据构建评论并保存到数据库
 if request.method == 'POST':
 # 获取请求中的评论数据构建评论表单
      comment_form = CommentForm(data=request.POST)
 # 如果通过表单有效性校验则构建评论数据并保存
 #  if comment_form.is_valid():
      new_comment = comment_form.save(commit=False)
      new_comment.post = post
      new_comment.save()
 else:
 # 如果请求类型不是POST，则构建空评论表单
 


  comment_form = CommentForm()

 return render(request, 
               'blog/post/detail.html',
               {'post': post,
               'comments': comments,
               'new_comment': new_comment,
               'comment_form': comment_form,
               'similar_posts': similar_posts })





def post_share(request, post_id):
 # 获取要分享的文章信息
 post = get_object_or_404(Post, id=post_id, status='published')
 # 设置发送状态为未发送
 sent = False
 # 如果请求是POST表示有提交表单
 if request.method == 'POST':
 # 通过EmailPostForm表单类获取请求中的表单数据后保存到form中
    form = EmailPostForm(request.POST)
 # 如果表单数据验证通过则发送邮件并将状态设置为已发送
    if form.is_valid():
      cd = form.cleaned_data 
# 构建请求路径
    post_url = request.build_absolute_uri(post.get_absolute_url())
 # 构建邮件标题
    subject = f"{cd['name']} recommends you read " \
                 f"{post.title}"
 # 构建邮件正文 
    message = f"Read {post.title} at {post_url}\n\n" \
            f"{cd['name']}\'s comments: {cd['comments']}"
 # 发送邮件
    send_mail(subject, message, '1931099959@qq.com',
                 [cd['to']])
 # 发送状态设置为真
 
 # 发送邮件，稍后完成
 # 发送状态设置为真
    sent = True
 else:
 # 如果表单数据验证未通过将表单设置为空
  form = EmailPostForm()
 # 渲染分享文章模板，并将文章、表单、发送状态信息传递给文章分享模板
 return render(request, 'blog/post/share.html', {'post': post,


 'form': form,
 'sent': sent})







def post_search(request):
  form = SearchForm()
  query = None
  results = []
 # 如果请求中有query字段则获取表单中的数据进行处理
  if 'query' in request.GET:
 # 获取表单
   form = SearchForm(request.GET)
 # 如果表单中的数据验证通过，即有效，则获取并处理
  if form.is_valid():
 # 获取搜索内容保存下来
   query = form.cleaned_data['query']
 # 根据标题和正文字段构建搜索向量并生成搜索字段，再根据搜索内容筛选出匹配内容保存
  results = Post.published.annotate(
 search=SearchVector('title', 'body')
 ).filter(search=query)
 # 将搜索结果渲染到搜索模板并返回
  return render(request, 
 'blog/post/search.html', {
 'form': form,
 'query': query,
 'results': results
 })







 
